101 Must-See Cosmic Objects: The Owl Nebula

Among the planetary nebulae in the high northern heavens, M97, the Owl Nebula, is the most famous. Pierre Méchain discovered it on Feb. 16, 1781, about 2.5° southeast of Merak (Beta [β] Ursae Majoris), noting it was difficult to see with crosshairs illuminated. Messier agreed, recording, “its light is faint.” The difficulty is not so much its brightness (magnitude 9.8), but that its dim light is spread across nearly 3.5′ of sky. Nevertheless, today the Owl is one of t